Key chain



FIG. 1 is a perspective view of a key chain.

FIG. 2 is a front elevation view thereof; the rear elevation view is a mirror image thereof.

FIG. 3 is a side elevation view thereof.

FIG. 4 is the opposite side elevation view thereof.

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is top plan view thereof.

The broken lines do not form part of the claimed design. 

CLAIM I claim the ornamental design for a key chain, as shown and described. 